Do solar panels compare well with other RE options?

Reed_Richards

When I was considering solar panels I looked at other renewable energy options such as a domestic wind turbine. But I could not find any company that wanted to install a wind turbine for me whereas there is a whole industry geared-up to install solar panels. So the solar panels went in at the beginning of March. Reviewing my generation figures so far I have averaged about 15,1 kWh per day. So (dividing by 24) that's an average of 630 W. You can certainly get small wind turbines that have a peak output that comfortably exceeds this, although I have no idea how a likely average would compare to the peak output. Minus the installation costs these turbines don't seem particularly expensive. But I suppose only a tiny fraction of the number of properties that could conveniently install solar panels could site a wind turbine easily. Then on another thread it was pointed out to me that if you have a stream going past then hydro-power might be a viable option. So are we mostly, like me, choosing our domestic RE sources based on the ease of installation rather than their economic (MoneySaving ) merits?

Martyn1981

I liked the idea of a small WT, but on checking my postcode is not suitable, and then over the last decade I've learned from reading the posts of on and off gridders with WT's. Now I would never consider one for an urban or suburban setting, there is simply too much turbulence.

To work well, you need about 100m of unobstructed clear ground between the WT and the direction the wind normally blows from, and mounted around 10m up, otherwise the WT will spend most of its time 'hunting' and not generating. Also WT's need a lot of love and care.

The small WT industry was quite large 10yrs ago, you may have seen sales people in B&Q and other places, but with the nickname of 'swindlesave' replacing the main company offering, that industry seems to have died. Suburban WT's were generating around £20 of leccy pa, and consuming a similar amount for their always on inverters.

VAWTS (vertical axis wt's) come up a lot, but many seem to just be crowd funding campaigns, and none yet have cracked the problems of turbulence in built up areas.

But, you could invest in a community wind scheme, or even larger national schemes, which I've done.

Similar problems exist for small scale hydro, especially low flow or low head situations, and the very high abstraction licencing that the EA charges.

To be blunt, its economies of scale, going bigger with WT's and hydro makes incredible economic sense, whereas there is little to no economies of scale* with PV, as regardless of the role, they are typically built at the same plants, to the same size for shipping and handling, and generate the same amount, though of course a large scale farm will optimise pitch and orientation.

*Not to be confused with economies of volume - yes 16,000 panels will cost less per panel, than 16 panels, but you don't get a bigger and better panel. [Additional caveat, bi-facial panels are obviously suitable for ground mount, but not roof mounting.]

Reed_Richards

Thank you for your interesting response, @Martyn1981. There's a strong wind blowing past at the moment; perhaps partially because I do have that elusive 100 m of unobstructed ground. I can see that economies of scale for wind power make good sense in one respect but although I can see large wind turbines on the horizon I don't get a discount on the electricity I buy-in (on the basis that it doesn't have to come very far). So generating electricity less efficiently at the point of use might in principle still beat large wind farms plus national grid. As for hydro, well what actually constitutes abstraction?

Martyn1981

Reed_Richards wrote: »

Thank you for your interesting response, @Martyn1981. There's a strong wind blowing past at the moment; perhaps partially because I do have that elusive 100 m of unobstructed ground. I can see that economies of scale for wind power make good sense in one respect but although I can see large wind turbines on the horizon I don't get a discount on the electricity I buy-in (on the basis that it doesn't have to come very far). So generating electricity less efficiently at the point of use might in principle still beat large wind farms plus national grid. As for hydro, well what actually constitutes abstraction?

I think any hydro device where water is diverted through it is abstraction, which seems a bit unfair to me. P-o-S raised the issue of an instream device like a waterwheel, but I've no idea what the legalities on that are, but hopefully better.

Funny you should mention about poorer domestic economics, as I once said that I thought domestic (small scale) PV was more 'economically viable' than large scale supply side (which is great, no criticisms from me) as the higher cost of demand side is more than balanced by the far higher (3 or 4x) value of retail leccy v's wholesale. I got 'trolled' for about 5yrs on that, each time the claim being I said domestic PV generation was cheaper.

So, yep, I agree about a small demand side WT being fine, if you can get one that's 'fine'. But do your research, check planning permission if you want to mount it high, and get recommendations for one that will deliver something akin to what is claimed. If nothing else, I'm sure it would be fun.

Please don't think I'm a critic of wind, it's my first love, but small scale is tricky, so look before you leap, but I'm not suggesting you don't leap.